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14802. Changes in the life history traits of the European Map butterfly, Araschnia levana (Lepidoptera: Nymphalidae) with increase in altitude
- Creator:
- Wagner, Kathrin D., Krauss, Jochen, and Steffan-Dewenter, Ingolf
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Nymphalidae, Araschnia levana, global change, altitudinal gradients, trophic interactions, geographical synchronisation, 2, and 59
- Language:
- English
- Description:
- Climatic conditions can modify the life history traits, population dynamics and biotic interactions of species. Therefore, adaptations to environmental factors such as temperature are crucial for species survival at different altitudes. These adaptive responses, genetically fixed or plastic (phenotypic plasticity), can be determined by physiological thresholds and might vary between sexes. The objective of this study was to determine whether the life history traits of the European Map butterfly (Araschnia levana) differ at different altitudes. A field experiment was carried out along an altitudinal gradient from 350 to 1010 m a.s.l. in a low mountainous region (Bavaria, Germany). 540 butterfly larvae were placed at different altitudes in 18 planted plots of their larval host plant, the stinging nettle (Urtica dioica). After three weeks the larvae were collected and reared under laboratory conditions. Developmental traits of the butterflies, mortality and percentage parasitism were measured. Larval development was generally slower at higher altitudes and lower temperatures and larval weight decreased with increasing altitude and decreasing temperature. However, there were no significant differences in pupation, adult lifespan and percentage mortality at the different altitudes and temperatures. Female larvae were heavier than those of males, and the pupal and adult lifespans were longer in females than in males. However, male and female butterflies reacted similarly to altitude and temperature (no significant interactions). None of the 188 larvae collected were parasitized. In conclusion, the phenotypic plasticity of European Map butterfly has enabled it to adapt to different temperatures, but the strategies of the sexes did not differ. and Kathrin D. Wagner, Jochen Krauss, Ingolf Steffan-Dewenter.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14803. Changes in the near-UV fluorescence excitation spectrum during protochlorophyllide photoreduction in etiolated cucumber cotyledons
- Creator:
- Durchan, M. and Lebedev, N.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Cucumis sativus L., energy transfer, protochlorophyllide reductase, and Shibata shift
- Language:
- Multiple languages
- Description:
- Fluorescence excitation spectra of different protochlorophyll(ide) (PChlide) a forms in intact etiolated cucumber cotyledons showed a pronounced increase in intensity of the 390 nm band in comparison with spectra of the pigment in Solutions. The native PChlide F657 also had an additional band at 360 nm in its excitation spectra, which disappeared after leaf homogenization and was restored by addition of dithionite. The restoration correlated with changes around 340 nm in the excitation spectrum of blue-green fluorescence. In consideration of this fact, the 360 nm band seems to correspond to energy transfer from NADPH to PChlide a. After the onset of irradiation a new band appeared at 380 nm in the excitation spectrum of the main pigment fluorescence, which was very similar to that found in the absorption spectinm of isolated Chl a. Moreover, in the Soret region the excitation spectrum had a double band splitting which disappeared only after the Shibata shift, simultaneously with the disappearance of the 360 nm band. Besides the well-known PChl(ide) F633, F642, and F657 forms, etiolated cucumber cotyledons háve emission at 673 nm. Its excitation spectrum was hardly distinguishable from the PChlide F657 fluorescence excitation spectrum in etiolated samples. In the irradiated plants this band had excitation spectrum of monomeric Chl a. The intensity of band at 673 run decreased and transiently increased after PChlide photoconversion. The dynamics of these fluorescence intensity changes under inadiation showed positive correlation both with PChlide F657 and with PChl(ide) F642, indicating the short wavelength Chl a preexistence in etiolated plants and its additional formation after the onset of irradiation.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14804. Changes in the non-photochemical quenching of chlorophyll fluorescence during aging of wheat flag leaves
- Creator:
- Hong, S.-S., Hong, T., Jiang, H., and Xu, D.-Q.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- diurnal variation, photo inhibition, photosystem 2 reaction centres, state transition, trans-thylakoid membrane proton gradient, Triticum aestivum, and xanthophyll cycle
- Language:
- Multiple languages
- Description:
- Non-photochemical quenching of chlorophyll fluorescence (qN) and its three components (qNf, qNm, and qNs) in the flag leaves of wheat grown in the field were studied by a fluorometer PAM-2000 on clear days. The diurnal variation patterns of qN in just fully extended (JFEL) and aging leaves (AL) were similar, but qNm declined markedly in JFEL while it remained at a relatively high level in AL under strong sunlight at noon. Furthermore, at midday qNf was higher than qNs in JFEL, but much lower in AL. The results show the relative contributions of different mechanisms in preventing the photosynthetic apparatus from photodamage change during leaf development. and S.-S. Hong ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14805. Changes in the Number of Nitrergic Neurons Following Kainic Acid Administration and Repeated Long-term Hypoxia
- Creator:
- Benešová, P., Langmeier, M., Betka, J., and Trojan, S.
- Type:
- article, model:article, and TEXT
- Subject:
- Kainic Acid, Nitric Oxide, Hypoxia, Hyppocampus, and Primaryx auditory cortex
- Language:
- English
- Description:
- Using histochemical analysis (NADPH-diaphorase) we have been investigating the influence of intraperitoneal administration of kainic acid (KA), hypoxia and combination of both these factors on neurons of the hippocampus and on the primary auditory cortex (PAC) in male rats of the Wistar strain. Kainic acid was administered to 18-day-old animals, which were exposed to long-lasting repeated hypoxia from the 2nd till the 17th day of age in a hypobaric chamber (for 8 h a day). At the age of 22 or 90 days, the animals were transcardially perfused with 4 % paraformaldehyde under deep thiopental anesthesia. Cryostate sections were stained to identify NADPH-diaphorase positive neurons that were then quantified in the hippocampus, in the dentate gyrus and in the PAC. In 22-day-old animals both hypoxia and KA increased the number of NADPH-diaphorase positive neurons in the hilus, CA1, CA3 areas of the hippocampus and in the PAC. On the contrary, KA given to hypoxic animals lowered the number of NADPH-diaphorase positive neurons in the dentate gyrus. In 90-day-old animals, hypoxia and KA given to both normoxic and hypoxic animals lowered the number of NADPH-diaphorase positive neurons in some areas of the central nervous system.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14806. Changes in the numbers of chromosomes and sex determination system in bushcrickets of the genus Odontura (Orthoptera: Tettigoniidae: Phaneropterinae)
- Creator:
- Warchałowska-Śliwa, Elżbieta, Maryańska-Nadachowska, Anna, Grzywacz, Beata, Karamysheva, Tatjana, Lehmann, Arne W., Lehmann, Gerlind U. C., and Heller, Klaus-Gerhard
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Orthoptera, Odontura, karyotype evolution, neo-XY, neo-X1X2Y, FISH, 2, and 59
- Language:
- English
- Description:
- Chromosomes of the males of five species of Odontura, belonging to the subgenera Odontura and Odonturella, were analyzed. Intensive evolution of the karyotype was recorded, both in terms of changes in the numbers of chromosomes (from 2n = 31 to 27) and the sex chromosome system (from X0 to neo-XY and X0 to neo-X1X2Y). Karyotype evolution was accompanied by tandem autosome fusions and interspecific autosomal and sex chromosome differentiation involving changes in the locations of nucleolar organizer regions, NORs, which were revealed by silver impregnation and confirmed by FISH using an 18S rDNA probe. O. (Odonturella) aspericauda is a polytypic species with X0 and neo-X1X2Y sex determination. The latter system is not common in tettigoniids. It possibly originated by a translocation of a distal segment of the original X chromosome onto a medium sized autosome, resulting in a shortened neo-X1 and a metacentric neo-Y. The remaining autosome homologue became the neo-X2 chromosome. This shift from X0 to neo-X1X2Y is supported by the length of the X chromosome and location of the NOR/rDNA. and Elżbieta Warchałowska-Śliwa, Anna Maryańska-Nadachowska, Beata Grzywacz, Tatjana Karamysheva, Arne W. Lehmann, Gerlind U.C. Lehmann, Klaus-Gerhard Heller.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14807. Changes in the payment for article publishing
- Type:
- article, model:article, and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14808. Changes in the personality profile of young women with latent toxoplasmosis
- Creator:
- Flegr, Jaroslav and Havlíček, Jan
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Toxoplasma gondii, behaviour, Cattell’s questionnaire, manipulation hypothesis, and permutation test
- Language:
- English
- Description:
- Latent toxoplasmosis is the most widespread parasite infection in developed and developing countries. I'he prevalence of Toxoplasma gondii infection varies mostly between 20 to 80% in different territories. This form of toxoplasmosis is generally considered to be asymptomatic. Recently published results, however, suggest that the personality profiles of infected subjects differ from those of uninfected controls. These results, however, were obtained on non-standard populations (biologists or former acute toxoplasmosis patients). Here we studied the personality profiles of 191 young women tested for anti-Toxoplasma immunity during gravidity. The results showed that the differences between Toxoplasma-negative and loxoplasma-posilive subjects exits also in this sample of healthy women. The subjects with latent toxoplasmosis had higher intelligence, lower guilt proneness, and possibly also higher ergic tension. The difference in several other factors (desurgency/surgency, alaxia/protension, naiveté/shrewdness, and selfsentiment integration) concerned changes in the variances, rather than the mean values of the factors.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14809. Changes in the photosynthetic characteristics and photosystem stoichiometries in wild-type and Chl b-deficient mutant rice seedlings under various irradiances
- Creator:
- Yamazaki, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, antenna size, Cl b-deficient mutant, photosystem stoichiometry, PSII heterogeneity, and rice (Oryza sativa L.)
- Language:
- Multiple languages
- Description:
- By using a wild-type rice (Oryza sativa L. cv. Norin No. 8) and the chlorophyll (Chl) b-deficient mutant derived from Norin No. 8 (chlorina 11), the present study monitored the oxygen evolution, contents of Chl a and b, β-carotene, and lutein in leaf and the contents of cytochrome f, and the reaction centres of photosystem I (PSI) and photosystem II (PSII) in thylakoids. The oxygen evolution, maximal quantum yield of PSII (Fv/Fm) and Chl concentration remained constant in both Norin No. 8 and chlorina 11 under 5 and 2% of full sunlight for six days. On the other hand, on the thylakoid level, the PSII reaction centre of chlorina 11 was more stable even under high irradiance, while approximately 40% decrease in levels of the PSII reaction centre occurred under 2% of full sunlight for six days. However, under such conditions, by regulating the stoichiometry of active PSII and PSI centres, the light absorption balance in both rice types was adjusted between the two photosystems. The present study attempted to examine whether the light absorption balance between PSII and PSI is altered to effectively conduct photosynthesis in the wild-type and Chl b-deficient mutant rice seedlings. and J. Yamazaki.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14810. Changes in the pools of carotenoids and protochlorophyll(ide) in etiolated cucumber (Cucumis sativus) cotyledons treated with norflurazon and KC 6361
- Creator:
- Jung, S., Kim, J. S., Cho, K. Y., and Kang, B. G.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- 5-aminolevulinic acid, β-carotene, carotenogenesis, irradiance, photosynthetic photon flux density, phytol, protochlorophyll, and xanthophylls
- Language:
- Multiple languages
- Description:
- Changes in the pools of carotenoids and protochlorophyll(ide) were investigated in etiolated cucumber cotyledons treated with norflurazon (NF) and an experimental herbicide KC 6361 (KC). Both the NF- and the KC-treated tissues considerably accumulated the colourless carotenes phytoene and phytofluene with a concomitant depletion of the coloured carotenoids lutein and β-carotene in darkness. However, the profiles of changes in chlorophylls (Chls) and carotenoids were different for the two herbicides. The plants were also influenced by the photosynthetic photon flux densities (PPFD's), with a more pronounced decline of Chl under high PPFD than under low PPFD. The ratios of protochlorophyll (PChl)/protochlorophyllide (PChlide) were greatly altered due to a decrease and an increase of PChl in the NF- and the KC-treated etiolated tissues, respectively, whereas the PChlide content was not significantly influenced by the inhibitors. Large increase of PChls in the KC-treated tissues seems to derive from the binding of accumulated geranylgeraniol (GG) equivalents, through carotenogenic inhibition, to PChlide. Therefore, the alterations of PChl and PChlide occurring under disturbed carotenogenesis may suggest an interaction between the biosynthetic pathways of Chls and carotenoids. In addition, the great proportion of PChl GG and PChl dihydro-GG in the KC-treated tissues implies that PChl formation is regulated at the level of hydrogenation. and S. Jung ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public